Proton-lead collisions are a type of high-energy particle collision that occurs when a proton beam is directed at a lead target. These collisions are studied in particle physics experiments to understand the interactions between protons and lead nuclei, as well as the properties of quarks and gluons within these nuclei. Proton-lead collisions are often used to probe the structure of nuclei, study the production of new particles, and investigate the properties of the quark-gluon plasma, a state of matter that is believed to have existed in the early universe. This research area is important for advancing our understanding of fundamental particles and the forces that govern their interactions.